There may be a situation when Skype for Business front end server despite of having enough memory performs very poorly and you can even see low memory errors in Event Log from SQL. In case the front end is hosted on virtual machine the first thing that has to be checked in such kind of scenario is MS SQL Server memory limits. These limits are set by Skype for Business Deployment Wizard at the moment of database installation and in case the virtual machine has dynamic RAM and amount of actual RAM was not maximum at the moment of deployment SQL Server memory limits could been set incorrectly. Continue reading
Feb 17 2017
Skype for Business SQL Low RAM condition
Feb 10 2017
Skype for Business, Asterisk and SIP REFER
If you don’t use VoIP gateway that “officially” supported by Microsoft and Skype for Business you may experience troubles in some cases as those devices may not interpret correctly SIP Refer messages sent by Skype for Business Mediation Server. The problem I’ve experienced in my environment was that when you activate “Call me at” feature in Skype for Business mobile client calls were immediately dropped after you had picked up your phone. I’ve used Asterisk as VoIP gateway and Skype for Business uses it for all calls to PSTN and cell carriers. Continue reading
Feb 06 2017
Configure logrotate for Asterisk logfiles on CentOS
logrotate is an utility specially designed for ease rotation of large numbers of log files. It allows automatic rotation, compression, removal, and mailing of log files. Each log file may be handled daily, weekly, monthly, or when it grows too large.
Normally, logrotate is run as a daily cron job. By default it lacks the configuration file for Asterisk logfiles. Here I’ll suggest an example but you may customize it based on your needs.
Jan 25 2017
How to Disable Administrative Shares in Windows
By default, Windows creates some hidden shared folders – administrative shares. These folders are identified by a dollar sign ($) at the end of the share name and so they are hidden. Hidden shares are those that not listed when you look at the network shares on a computer in File Explorer’s Network node, or using the net view command. Windows 10, Windows 8, Windows 7 and even Vista and XP create hidden administrative shares that administrators, programs, and services can use to manage the computer environment on the network. Continue reading
Jan 20 2017
Cannot publish topology changes. Conference directories still exist on a pool that would be deleted. Remove the conference directories before continuing.
During migration to a new pool there was a need to remove old Front End servers from topology. After removing them from topology builder I received this error: “Cannot publish topology changes. Conference directories still exist on a pool that would be deleted. Remove the conference directories before continuing”. Quick look into the error showed that topology builder had a dependency on a conference service installed on one of the servers that wasn’t cleaned up properly. Continue reading
Jan 14 2017
Upgrading MySQL 5.1 to 5.7 service failed to start
After MySQL upgrade from 5.1 to 5.7 on Centos 6.8 the mysqld service failed to start. In /var/log/mysqld.log I got the following:
2017-01-14 17:19:33 2175 [ERROR] InnoDB: auto-extending data file ./ibdata1 is of a different size 640 pages (rounded down to MB) than specified in the .cnf file: initial 768 pages, max 0 (relevant if non-zero) pages!
2017-01-14 17:19:33 2175 [ERROR] InnoDB: Could not open or create the system tablespace. If you tried to add new data files to the system tablespace, and it failed here, you should now edit innodb_data_file_path in my.cnf back to what it was, and remove the new ibdata files InnoDB created in this failed attempt. InnoDB only wrote those files full of zeros, but did not yet use them in any way. But be careful: do not remove old data files which contain your precious data!
2017-01-14 17:19:33 2175 [ERROR] Plugin ‘InnoDB’ init function returned error.
2017-01-14 17:19:33 2175 [ERROR] Plugin ‘InnoDB’ registration as a STORAGE ENGINE failed.
2017-01-14 17:19:33 2175 [ERROR] Unknown/unsupported storage engine: InnoDB
2017-01-14 17:19:33 2175 [ERROR] Aborting
Jan 10 2017
Skype for Business. Move Central Management Store
There is a need to move Central Management Server to a new pool as the existing one is going to be decommissioned. SQL Backend consists of two MSSQL 2014 Servers running in AlwaysOn Cluster. While running Move-CsManagementServer commandlet with –WhatIf key I got an error:
Cannot move Central Management Server. The new Central Management Store located at “AlwaysOnListener.domain.com” is not accessible.
Needless to say that listener’s FQDN is available as well as both SQL servers. Permissions is not the case as well as I run that command under user with RTCUniversalServerAdmins group membership. Continue reading
Jan 05 2017
Install Skype for Business Prerequisites
Skype for Business Server 2015 is available now, along with a new set of demands to install it right on your Windows Server.
Here are the recommendations for each Windows version:
Windows Server 2008R2: Microsoft recommends that you only install Skype for Business Server 2015 on Windows Server 2012 or 2012R2. However, if you’re in-place upgrading from an existing installation of Lync 2013, you might like to use your existing Windows 2008R2 server. The following procedure assumes you already have Lync 2013 installed on your system, so all prerequisites should already be installed. Continue reading
Jan 04 2017
Understanding Skype for Business DNS Records and Autoconfiguration
Skype for Business DNS Records are one of critical components of the whole infrastructure. Skype for Business uses two types of DNS records: A record and SRV record.
The DNS is often deployed as “split-brain” DNS deployment: the same zone name is deployed internally and externally but with different (internal or external) IP-addresses for the same entries.
Thus Skype for Business clients will get information only from their zone, so if external client is trying to connect to Skype for Business server, it will resolve the entries to the external IP-addresses, if it’s from internal network then it will resolve the DNS entries to internal IP-addresses using the internal DNS server.
If you are not using “split-brain” DNS you can create a zone for each required DNS records pointing it to the internal IP-address. Continue reading
Dec 19 2016
Configuring Gmail as a Sendmail email relay
In this article I will show how to configure gmail to be an email relay for your linux server with sendmail MTA. This allow you to send letters from your bash scripts, hosted website or from command line using mail command. Other examples where you can utilize this setting is for a notification purposes such or failed backups etc. Sendmail is not the only Mail Transport Agent that can be configured to use gmail account Postfix, exim , ssmpt etc. can be configured as well. The guide below was created on Debian. Continue reading
Stay tuned! :)
